This is what I have been working on recently... its an improved version of my previously posted Detent BB gun. This time it feeds good and has a low rof so I can shoot semi or full auto! Inside there is a 25.5" tightbore barrel 6.03mm ID. I am currently shooting .2s and they fly pretty straight. I made a hop up for it but the bb's naturally curve without it. I think it is because of the notch in the barrel where the hop up unit normally goes. So, if I want severe hop up I can use my homemade one. But for normal hop up, I dont really need hop up Here is a video. Cheers [youtube]http://www.youtube.com/watch?v=N2vjWQbOfZs[/youtube]

Thanks Probably not, I've tried to think of simple ways to do it but to no avail. The chamber is a 1/4" nipple so the bbs don't feed in a straight line, and I can't think of a compact way to do it, and it needs to be compact because I'm shelling it.

If you extended the back part of the chamber then you could put more bbs in, in theory. Good gun by the way, and I love your use of the two fire-extinguishers. on average how many shots do you get from them without re-filling?

I am thinking about extending the chamber, but the bigger the chamber is, the more air it uses. Which leads me to your question... this gun is incredibly efficient on air, I barely pull the trigger and it will shoot. I can't give you an exact number, because it varies depending on if I am running full or semi auto. But I can tell you that this tank takes about 20 seconds to run low through a blowgun, unregulated, at 150 psi

Thats a good air usage for 150psi!, as for the chamber enlargement agreeably, but this is your call. you must decide whether chamber capacity is more important than air consumption. if you just made it about 5-10cm longer then the effects would not be massive on the performance but it would enlarge the cap quite a bit.

Airsoft BBs are the most reliable I've used for a detent mechanism. Nice work but I'm sure you can do better I would make a bigger diameter chamber chat would give BBs space to agitate and reduce jams.

I also respect your honesty at not editing out the misfires, and lol @ your sibling.

I want to use a 1/2" chamber but before I wasn't sure if it would squish the washers enough. I think it will though. Its just more fittings I need to go buy we'll see. I do want to use a 1/2" chamber though.

I kept the misfires specifically for the forum I hoped someone would comment about it, with possibly solutions, like you did. Thanks, and my brother wanted me to keep that part in lol

I would make a bigger diameter chamber chat would give BBs space to agitate and reduce jams

that or do exactly the opposite - reduce the chamber diameter to ~9mm or so... IIRC that resulted in improved performance (no jamming) but you might have to reduce flow to the chamber (as lowe volume to fill results in higher ROF)

That would work, but feeding like that results in a direct path to the breech, obliterating the semi auto option. I think that would raise the rof significantly unless I really decrease flow, but it is still an idea. Thanks guys. At this point I could enlarge or "smallen" (:D) the chamber...

I've been looking forward to seeing the gun work, looks great! I like the simplicity of the gun. Props on using the tightbore barrel, that's something I've been wanting to do myself.

Have you thought about adding a needle valve to control the airflow? I find that it takes some of the guesswork out of trying to control the rpm, versus having to gingerly squeeze the blowgun.

I would also suggest adding more ammo capacity. I'm intrigued by how you'll solve the jamming problem, the same problem has been plaguing my .177 gun, which has a 1/2" brass pipe chamber.

@JSR, I'm not sure I understand how he would incorporate a coiled magazine? Would it have to use a blowforward bolt (or something of that ilk) to avoid just dumping bb's into the chamber/heavily constricting airflow? (I ask because I'm in the same situation as Gunfreak)

Have you thought about adding a needle valve to control the airflow? I find that it takes some of the guesswork out of trying to control the rpm, versus having to gingerly squeeze the blowgun.

I am going to try to make one. Just a fitting that is plugged then I will make a small hole in the plug. How big should the hole be?

I would also suggest adding more ammo capacity. I'm intrigued by how you'll solve the jamming problem, the same problem has been plaguing my .177 gun, which has a 1/2" brass pipe chamber.

If 1/2" doesn't work for your .177, it probably won't work for me either

@JSR, I'm not sure I understand how he would incorporate a coiled magazine? Would it have to use a blowforward bolt (or something of that ilk) to avoid just dumping bb's into the chamber/heavily constricting airflow? (I ask because I'm in the same situation as Gunfreak)

Just a coiled chamber instead of a big one. It would eliminate jams because the chamber is only wide enough for one bb. Coiling it allows it to be longer in a smaller space.